Not many websites really go into detail, but if you really want to save money, try a metal roof which will decrease your overall household temperature. Asphalt (shingled) roofs absorb heat, but metal reflects. Although it's expensive it's sure to pay off in the end!
When buying a portable air conditioner, you should worry about how much energy in which they consume. Seen as they are DC, they will not consumer as much as say an AC air conditioner which is powered from the mains.
You will use more gas when your air conditioner is running.
It can, all air conditioners should have a energy rating on it, the new ones take less energy then older ones. They consume energy in order to make us confortable during the hot days.
The air conditioner itself does not release any carbon or carbon dioxide. But if the energy to power the air conditioner comes from a coal fired power plant, it takes more energy to reduce the temperature of a room than it does to heat it.
There are no air conditioner's here currently available that run only on solar energy.
This website will have all the info you need: http://www.wisegeek.com/how-much-energy-does-air-conditioning-use.htm
It varies from air conditioning unit to unit. However, the exact energy usage will be on a name plate on the air conditioner. Look for a rating in either amps or watts.
Your dog will survive perfectly well indoors without the air-conditioner on - regardless of whether it's winter or summer ! Air-con units are the biggest waste of energy on this planet !
Air conditioning equipments consume 0.5 KW electricity per Kilowatt refrigeration.
That'd be 3256.23
About the same as for a window air conditioner.
I suggest that you put your air conditioner on low or use the fan on the air conditioner because it uses less energy. Another thing you could do is take a regular fan and put in the window to get air flow.